Understanding the mechanical stability of granular‐armored liquid marbles is prerequisite for their applications including encapsulation, sensors, microreactions, and miniaturized liquid storage. Most liquid marbles are armored with agglomerated granular structure which complicates the wetting and interacting states of particles, hence, impeding one from understanding the effect of granular size on the mechanical stability of marbles. In this work, using a custom‐built platform to examine the liquid marbles armored by a single layer of uniform grains, it is revealed that larger microsized grains produce stronger liquid marble. This finding is attributed to the gravity‐induced capillary attraction which dominates the interaction of particles and provides additional tension to the granular network of the marble surface, which enhances the mechanical stability of marbles. In addition, different granular network structures are formed at the marble surface by using a binary mixture of monodisperse grains, and their effect on the mechanical stability of marbles is explored. The understandings offer important insights for application involving liquid marbles and provides guideline to formulate robust marble‐based products.

Ionic organic-inorganic hybrid lead halide perovskites are prone to degrade at elevated temperatures, especially in the presence of water moisture. This grand challenge heavily impedes the outdoor application of high-efficiency...

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Chrysene is a readily available material for exploring new polycyclic aromatic hydrocarbons (PAHs). In this study, two chrysene based azahelicenes, nine‐membered BA7 and ten‐membered DA6, are constructed by intermolecular oxidative annulation of 6‐aminochrysene and intramolecular annulation of N6,N12‐bis(1‐chloronaphthalen‐2‐yl)chrysene‐6,12‐diamine, respectively. The hexylated BA7 and DA6 and their brominated products were undoubtedly characterized by single crystal XRD. Subsequent amination with bis(9‐methyl‐9H‐carbazol‐3‐yl)amine (BMCA) electron donor afforded D‐π‐D‐type semiconductors BA7‐BMCA and DA6‐BMCA with beneficial properties to act as hole transport materials for perovskite solar cell. Compared with 19.4 % champion power conversion efficiency (PCE) of BA7‐BMCA based device, a higher PCE of 20.2 % for DA6‐BMCA counterpart may be attributed to its S‐shaped double helicene‐like linker with extended π‐conjugated system.